Sensitivity of AHU power consumption to PCM implementation in the wall-considering the solar radiation

This study examined the efficacy of PCM implementation in the wall on the thermal performance of the air handling unit (AHU). For this, a PCM layer (2 cm) was incorporated into the base wall with a thickness of 23 cm to investigate the PCM presence efficacy on heat transfer reduction. Considering the solar radiation effects on the building envelope, the sensitivity of the heat transfer reduction to the wall positions toward the cardinal direction was inspected. Based on the numerical results, placing PCM close to the outside space outperformed the PCM close to the interior space. Owing to PCM incorporation, the maximum and minimum heat transfer reduction was 27% and 5%, respectively. To examine the effect of PCM properties, eighteen PCMs were utilized and it was found that the effectiveness of the PCM within the wall in reducing heat transfer intensified with reducing the thermal conductivity. By adding PCM to the wall, less heat is transferred to the interior space in July and therefore the AHU cooling coil load is diminished. Calculations show that installing PCM on the wall can reduce the cooling coil power up to 33%. The effect of wall direction on the usefulness of installing PCM inside the wall is significant.